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ehaugw

MK17 or MK20 replica.

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Hey people!

 

I am considering to pick up air soft as a hobby, and for that I need a gun. I don't have much experience, so I don't know which producers are good and which are not.

 

I have been looking around for a while, and really can't make my mind. I saw a gas operated MK17 standard from WE-Tech that has solid reviews.

http://www.evike.com/products/57579/

The only issues I have with this gun is that I would prefer a SSR if possible, and I am a little bit sceptical to using propane as a propeller (because it is flamable).

 

I have also been looking at these two:

http://airsoft.tiger111hk.com/p23585/WE-MK20-SCAR-H-Sniper-Support-Rifle-SSR-AEG-(Tan)/product_info.html

http://www.evike.com/products/36060/

 

The problems with these are that number one has some ugly colors (might be just on the picture), and number two has 10% lower FPS which means 10% more inaccuracy due to wind and bullet drop.

 

What I ask you about is a good SCAR-H, preferably an MK20 or at least a stock like this:

http://www.americanspecialops.com/special-ops-weapons/mk-20-mod-0-ssr.php

that fires at a high velocity, with a good accuracy, from a respected producer. The max price should be around 500USD for the rifle excluding everything else.

 

Thanks for all your time, in advance :)

 

Ps. I do not want a powerful gun to hurt people up close, but for accuracy purposes only. I got a side arm for closer engagements.

Edited by ehaugw

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First go and play a few skirmishes at your local field with a hire gun. That way you'll get an idea of what role you want to play, get a chance to handle a few different guns, and also find out what fps limits your field has.

Fps has pretty much no relation to accuracy. That is down to quality of hop, barrel and ammunition.

GBB (gas blow back) guns can be fussy, a little tricky to maintain and also are affected by temperature, to the point where they may not operate in cold weather. For a first gun look at an AEG. Upgradable, easy to maintain and reliable.

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Playing a few scirmishes sounds like a good idea, just to make sure I actually enjoy long range engagements with BBs.

 

Also, after reading a bit, an electric gun seems like a very good choice, so thanks for that confirmation!

 

When it comes to accuracy, hopups, barrel quality, length, and much other factors affects the final results, and one of these factors is bullet speed. The less time the bullet is in the air, the less it will be affected by the wind and gravity.

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Playing a few scirmishes sounds like a good idea, just to make sure I actually enjoy long range engagements with BBs.

 

Also, after reading a bit, an electric gun seems like a very good choice, so thanks for that confirmation!

 

When it comes to accuracy, hopups, barrel quality, length, and much other factors affects the final results, and one of these factors is bullet speed. The less time the bullet is in the air, the less it will be affected by the wind and gravity.

 

You have some misconceptions. Let us pass some more details to you.

 

Propane as a propellant is not a major issue unless your location has an ordinance against unrestricted discharge of that gas. While propane is "flammable" you need a lot of it concentrated in a very small area to have it ignite with a flame source. then the issue is not some much because the valve does prevent open venting of that gas. However, did you know the old propellant for Airsoft guns, "refrigerants" was also flammable too? So...you can't get away from it on a safety level.

 

As for your concept of wind and gravity on a projectile. There is no place that you can get away from Gravity. That is why hop-up was developed to maximize flight of the bb using the Magnus Effect. Get a good spin...it can hold off gravity for an extra 10-30 yards.

 

As for wind...compensate with a heavier round. A heavier slower round will travel a lot further than a lighter faster round. This is only true when all aspects are accounted for in an Airsoft guns entire "System" and not just the bb alone.

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You have some misconceptions. Let us pass some more details to you.

 

Propane as a propellant is not a major issue unless your location has an ordinance against unrestricted discharge of that gas. While propane is "flammable" you need a lot of it concentrated in a very small area to have it ignite with a flame source. then the issue is not some much because the valve does prevent open venting of that gas. However, did you know the old propellant for Airsoft guns, "refrigerants" was also flammable too? So...you can't get away from it on a safety level.

 

As for your concept of wind and gravity on a projectile. There is no place that you can get away from Gravity. That is why hop-up was developed to maximize flight of the bb using the Magnus Effect. Get a good spin...it can hold off gravity for an extra 10-30 yards.

 

As for wind...compensate with a heavier round. A heavier slower round will travel a lot further than a lighter faster round. This is only true when all aspects are accounted for in an Airsoft guns entire "System" and not just the bb alone.

I wasn't aware about what kind of gass you used for airsoft earlier, I am new to the whole thing.

 

When it comes to ballistics, I am not new to it at all. I am on my fourth year on a master in Math and Physics, so there is no need to teach me about how a plastic bullet travels in air, we got professors to do that job. Even though you are right on all points, bullet velocity is a factor. If a bullet is twice as fast, it will use half the time to get to the target (given that you have a heavy round that isn't affected too much of air drag (don't know what the English term is, English is my secondary language). If it uses twice as much time, it will be affected four times as much by gravity S = (v_o * t + 1/2 a* t^2). This can of course be compensated for with a hop up as you say, as well as scope zeroing. Also, if it is windy outside, a doubled travel time will increase inaccuracy due to wind by a number between two and four depending on if the bullet reaches the wind speed or not.

 

If couse, the issue with the wind can be compensated for with a heavier round, as you say, but if you double the weight on the bullet, the bullet speed will be divided by the square root of two, which is a huge difference (also, this will lead to twice the bullet drop due to gravity).

 

In adition to this, the slower the bullet is, the easier it will be to dodge it when you see it coming.

 

Sorry if I act like a prick, but I didn't sign up on this forum to be told that I don't know what I am planning to do for my living, but to get help with picking the right rifle on my terms, I am the one who is gonna pay for it in the end.

 

Ps. Feel free to correct me if I am wrong about the physics part.

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What you're not taking into account is that we're not firing 'bullets'. We're shooting a lightweight, non ballistic plastic ball. The hop unit aplies the backspin that generates the Magnus effect lift that counters the effect of gravity, hence Airsoft rounds do not follow a ballistic trajectory.

Also we are dealing with a fixed energy system, at least in terms of linear kinetic energy. You are limited to a muzzle velocity measured with a particular weight projectile. Higher weight, lower muzzle velocity. By if you calculate the energy decay of the heavier BB the maths comes out in favour of the heavier ball. A 0.3g round will reach 50m before a 0.2g round fired at the same energy, and when it gets there it will still be travelling with a fair percentage of its initial velocity while the 0.2g round is ready to drop out of the air. The heavier round also has the advantage that it can be given a much higher initial rotational momentum in addition to its linear momentum. Therfore when it reaches 50m it will also still be generating lift (Magnus effect) and hence following its mostly flat flight (notice I didn't call it a trajectory).

As for seeing it coming, it's a game played at ranges up to around 65m with full auto guns, and perhaps up to 90m with single shot bolt action rifles. If people dodge, get better and get closer. The heavier ball will reach ranges the lighter 'faster' ball can't, and over the second half of the ranges we shoot at get there faster too. Plus I use black ammo in my sniper. I can't track it in the scope, but I know I'll hit what I aim at. And if I can't see it neither can my target.

You have much to learn young Padawan... ;)

 

And while we're at at...

After about 200mm, barrel length has almost zero effect on accuracy in Airsoft guns. Bore quality is far more important, as is the quality of the BBs.

The difference in time to target at the extreme end of effective full auto Airsoft ranges is tiny for what seem like quite different muzzle velocities, less than 0.2s difference for initial velocities of 300 & 400fps.

Edited by Hangtight

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You say "Also we are dealing with a fixed energy system, at least in terms of linear kinetic energy".

I say "if you double the weight on the bullet, the bullet speed will be divided by the square root of two"

 

Given that E = m*v^2, we are saying exactly the same.

 

 

You say "By if you calculate the energy decay of the heavier BB the maths comes out in favour of the heavier ball."

I say "given that you have a heavy round that isn't affected too much of air drag",

and "If couse, the issue with the wind can be compensated for with a heavier round"

 

It is implied that we already use heavy rounds, I already agreed that heavier rounds helps out, because relative to the bullet, the atmosphere moves quite fast, and is a "wind".

 

 

You say " A 0.3g round will reach 50m before a 0.2g round fired at the same energy"

I don't know the drag coefficients for the bullets so I can't give any numbers about this, but it sounds very reasonable considering the balls are light weight and does not have an ideal shape. And I have never said anything else.

 

 

You say " when it gets there it will still be travelling with a fair percentage of its initial velocity",

I reply "no :pain: sherlock, it has a lower speed and thereby less drag, and a higher mass which means less acceleration due to F=MA."

 

I really don't see who/what you are trying to argue against. If you read my previous commend carefully, you will see that we say the same thing. Doesn't seem like the padawan has much to learn at all, except for one point, which is how the higher bullet gets a rotation. My guess would be that the angular momentum would be the same for all bullets, which means that the heavier ones rotates slower.

 

All in all, if you are trying to argue against the fact that a higher velocity isn't advantageous, there is something seriously wrong going with your logic.

 

EDIT: I believe hopups are small rubber at the beginning of the barrel, right? In that case I am quite sure it's a non-slip situation with the bullet, giving every bullet would get the same rotation.

 

EDIT v2: The heavier bullet will travel leave the hopup at a lower speed, giving it a lower rotation, which should give all the bullets the same angular momentum as I first said.

Edited by ehaugw

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The difference in time to target at the extreme end of effective full auto Airsoft ranges is tiny for what seem like quite different muzzle velocities, less than 0.2s difference for initial velocities of 300 & 400fps.

That's something you pulled out of your anus. It depends on distance to the target. At some point the 300 fps won't even reach the target, but the 400fps will, which means it takes infinitively more seconds to reach the target.

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You adjust the hop up to give the amount of rotation that will generate the correct amount of lift to counter gravity. The fact you can actually adjust it should have led you to the conclusion that it's NOT a zero slip system.

Because you can adjust the hop to give a flat flight with varying weight BBs when gravity is a constant, should have led you to the conclusion that for a level flight the heavier BB would need additional backspin. Factor that with the increase in rotational inertia of the heavier sphere.

This is why we R hop, flat hop, S hop etc. Also bear in mind that even the best BBs don't have a completely uniform mass distribution. Obviously a BB travelling at an initial 350fps is going to be more effective than one travelling at walking pace, but velocity isn't everything. Above certain velocities weird aerodynamics happen that upset the stability of the system. We have to keep energies down for safety reasons. My sniper will shoot a 0.2g BB at 500fps, but I use 0.4g (350fps for the same energy). Maximum effective range is around 85m. My full auto guns fire 350fps with 0.2g for a maximum effective range of maybe 50m. However I use 0.28g at under 300fps but they reach out to 65m. But because my guns are well set up I have the same effective range as a semi auto only DMR which at my fields can shoot 400fps (0.2g),plus I have the advantage of 20 rounds per second.

Mainly what I'm trying to say is, don't get hung up over fps. An AEG is a system, and when it all works together perfectly, your gun can shoot 50fps lower than someone else's but still out range them and be more accurate.

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That's something you pulled out of your anus. It depends on distance to the target. At some point the 300 fps won't even reach the target, but the 400fps will, which means it takes infinitively more seconds to reach the target.

Been doing this a while. I build my own guns from scratch and I skirmish regularly. Perhaps a while ago I had a similar attitude to yourself, but at least I was never rude. Perhaps go and gather some experience before you are so dismissive of others.

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I read wrong. I though you said that a heavy bullet would always spin faster, and that is what I couldn't make any sense off. I do agree that a heavier bullet would require more backspin to maintain a straight line tho.

 

Me being rude doesn't make it any less true. Where did you get <0.2s from?

 

When it comes to airsofts, I have owned, and even made my own airsoft from scratch, and used it for many years with different kinds of bullets, hop up systems and so on. Please don't assume I am an idiot and tell me what I need, but rather help me finding what I ask for.

 

If you wonder why I am rude, let me explain why. I get kinda pissed when people read only half my comment, and say I am wrong on some point, when we are essentially saying the same thing. It is a typical behaviour on forums, someone always has to pick on others, even tho they are saying the same thing, instead of helping out with what the OP asked for.

 

Also, you call me a padawan, despite studying physics at the best university in Norway for four years, and desipte the fact that everything we have said to eachother is essentially the same thing. This is what really tilted me.

 

 

Anyway. I am aware that you are trying to help, and I appriciate it. You have spent a lot of time explaining stuff, but that is not what I asked for. If I remember right, I asked for a SCAR, not a physics class.

When it comes to airsofts, I have owned, and even made my own airsoft from scratch, and used it for many years with different kinds of bullets, hop up systems and so on. Please don't assume I am an idiot and tell me what I need, but rather help me finding what I ask for.

 

 

EDIT:

 

You said "Perhaps go and gather some experience before you are so dismissive of others."

 

How am I dismissive? As I already said, we are saying exactly the same.

Edited by ehaugw

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Also...some of us here have been playing airsoft longer than some players have been alive. And some are just as educated as you are, with decades of first hand experience. So...we are NOT making things up. We are here to discuss and educate, not belittle, so don’t take it as an offense. But, their seems to be a written language barrier.

 

Airsoft bbs are ~6mm balls. They are not bullets. We kindly ask you to stop calling them bullets. These are balls that are propelled from a “blowgun”. Airsoft bbs Angular momentum does Not follow the path of trajectory. It is against the trajectory path in an aspect of back spin, which ties into the Magnus Effect, which a bullet flight path does not abide by.

 

Then there is the Law of Inertia and the 40% weight increase in a bb is quite significant in maintaining is range and accuracy.

 

WE Gs will not work very well in Norway...Thermodynamics of a Gas gun is hampered by temps, low temps.

Unless you Ice Pick (valve) the WE SCAR...it will only function normally about 25C.

 

Stay with an AEG. However, they do not make a Mk20 in Airsoft. I honestly wouldn't waste the money having cosmetic changes either in a MK20. Get the VFC SSR and set it for your field limits.

Edited by Guges Mk3
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Also...some of us here have been playing airsoft longer than some players have been alive. And some are just as educated as you are, with decades of first hand experience. So...we are NOT making things up. We are here to discuss and educate, not belittle, so don’t take it as an offense. But, their seems to be a written language barrier.

 

Airsoft bbs are ~6mm balls. They are not bullets. We kindly ask you to stop calling them bullets. These are balls that are propelled from a “blowgun”. Airsoft bbs Angular momentum does Not follow the path of trajectory. It is against the trajectory path in an aspect of back spin, which ties into the Magnus Effect, which a bullet flight path does not abide by.

 

Then there is the Law of Inertia and the 40% weight increase in a bb is quite significant in maintaining is range and accuracy.

No offense taken, you have impeccable attitude (unlike me). I will hereby call them BBs. I am aware that the BBs spin backwards and not sideways, and that it causes an force pointing upwards on the BB.

 

With all due respect, I want to say that bullets are also affected by the Magnus Effect, but in a completely different way. If the wind is strong when you shoot, you must obviously adjust your scope horizontally to compensate for the wind, but you must also adjust the scope slightly vertically, due to the Magnus Effect.

 

 

 

If you allow me to get back to the topic, my mind has changed. I still want a SCAR, but I have other priorities (most important on top):

1) It's an quality AEG.

2) No wires should be exposed when you fold the stock.

3) It delivers about 1.5 joules per BB (to not confuse anyone about fps, bullet weight etc).

4) It's <500 USD.

5) It's tan, not black.

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OK, maybe we got off on the wrong foot, but just so you know where I'm coming from... Four years at university, 20 years experience as an engineer. Knowing the maths is one thing, but you need to make sure your assumptions are correct before you proceed.

And to be fair your opening comment was that you don't have much experience...

If you want a SCAR go Tokyo Marui or VFC but not recoil models. Be aware that they can be improved, but there isn't a huge market for genuine upgrade parts, with some components (air nozzle for one of the top of my head) being proprietary. They are also big heavy guns. They look fantastic, but can become quite cumbersome for a full days play.

Folding stock models have conductive bushes in the hinge. The are a high resistance point and also fail. There isn't really any way around this without having exposed wires when the stock is folded.

Edited by Hangtight

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I excel at getting off on the wrong foot with people :(

 

"Knowing the maths is one thing, but you need to make sure your assumptions are correct before you proceed." - words to live by!

 

That sounds like some good advice. I have been looking at some VFC models, and they look very appealing. I haven't found any models by Tokyo Mauri tho, could I please have a link?

 

Also, the part about big heavy gun is great. I do this to get fit xD

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http://mackila.com/airsoft/atp/

 

There's something slightly amiss with the scaling of his range calculations, but the 'trajectories' and time /distance graphs correspond very closely with real world measurements. Particularly the bits where I got the 0.2s from. The were checked using Audacity to analyse the muzzle report and the sound of the BB hitting a steel plate at 60m range, including adjustment for the speed of sound and the position of the microphone (which made a whole 0.3% difference to the result).

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Not a great picture, but you can see the contacts.

 

https://www.fire-support.co.uk/product/vfc-scar-base-plate-for-hinge-tan

 

There's nothing to provide a consistent pressure to the contact, and they are open so prone to corrosion and the ingress of dirt.

 

http://img.redwolfairsoft.com/upload/review/182/VFC-AEG-SCARBK-DT3L.jpg

 

And here's how Marui do it.

 

http://www.anakchan.com/TM-SCAR-L/TM-SCAR-L07.jpg

 

Which doesn't look too terrible.

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I am back, for 2 reasons.

 

1) to tell hangtight that I am sorry for being a :censored2:. I read my posts now, and I don't like what I read.

 

2) to get an answer on a question Google can't answer:

 

"Hi again, people.

 

I am considering to buy a MK17 from Vega Force Company. It has a solid exterior, good materials, and nice features like no exposed wires when you fold the stock. However, I do now know what's included in the package. Some people claim they got a full steel flash hider with the gun, some people say they have to buy it separately, and some people claim it's impossible to remove the orange tip, and that a flash hider won't fit on it.

 

Also, some guns benchmark 400 FPS, while others benchmark 360 FPS.

 

Last but not least, I heard that there is an American version that doesn't have all the serial numbers etc printed on it.

 

My question is: where can I buy a VFC with all serial numbers and trademarks, that is compatible with a stroll flash hide, and how can I tell if he flash hider is included or not?"

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